The present application relates to an optical shaping apparatus for forming a cured layer by irradiating light to a photo-curable resin and forming a three-dimensionally shaped object of a desired shape by laminating the cured layers, and a shaping base that is used in the optical shaping apparatus and supports a three-dimensionally shaped object.
Heretofore, an optical shaping apparatus for forming a shaped object of a desired shape by using three-dimensional CAD (Computer Aided Design) data has been widely known.
As optical shaping methods used for the optical shaping apparatus, a free liquid level method and a regulated liquid level method are known in general.
Japanese Patent Application Laid-open No. 2007-90619 (paragraphs [0004] to [0006], FIGS. 4 and 5; hereinafter, referred to as Patent Document 1) discloses an optical shaping apparatus using the free liquid level method. In the optical shaping apparatus, a photo-curable resin is injected in a resin container, and a table (shaping base) is placed nearly below a liquid level of the photo-curable resin. Light is irradiated from above the liquid level (free liquid level) of an uncured resin above the table, and thus a first cured layer is formed on the table. Next, the table is lowered, light is irradiated again from above the liquid level of the uncured resin, and a second cured layer is formed on the first cured layer. By repeating those operations, a three-dimensional model (three-dimensionally shaped object) is formed on the table.
In the case where the free liquid level method is used, since the liquid level of the photo-curable resin is open to the atmosphere, the liquid level fluctuates when the table is lowered, for example. Therefore, there arises a problem that it may be difficult to form a three-dimensionally shaped object with high accuracy. For that reason, in the optical shaping apparatus disclosed in Patent Document 1, a squeegee is moved on the liquid level to uniform the liquid level of the photo-curable resin.
As described above, the fluctuation of the liquid level becomes a problem in the free liquid level method. In this regard, there may be a case where the regulated liquid level method of regulating the liquid level of the photo-curable resin is used.
Japanese Patent Application Laid-open No. 2000-043150 (paragraph [0007], FIG. 12; hereinafter, referred to as Patent Document 2) discloses an optical shaping apparatus using the regulated liquid level method. In the optical shaping apparatus, a photo-curable resin is injected in a resin container including a transmissive member such as a glass plate at a bottom surface thereof, and a stage (shaping base) is placed in the vicinity of the transmissive member. Light used for curing the photo-curable resin is irradiated from below the transmissive member. By the light, an uncured resin between the transmissive member and the stage is cured and thus a first cured layer is formed. After the first cured layer is formed, the stage is elevated to form a second cured layer. By repeating those operations, a three-dimensional object (three-dimensionally shaped object) is formed.